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Teasel Project


Project Leader: Brian RECTOR



Research Objectives and Methodology


Teasels have never been targeted for biological control before and they represent an ecological system for which very little basic or applied research has been performed or even proposed. Research required for the successful implementation of this program spans the fields of entomology, acarology, botany, ecology, horticulture, genetics, and molecular biology, as well as the effective integration of these fields. This array of relevant studies and disciplines may produce several different lines of inquiry being pursued simultaneously in anticipation of their convergence as the research progresses.


Objectives of this project include:


1) Identify primary pool of biological control candidates (BCCs) of teasels.

a) survey literature for information on herbivores and plant pathogens of teasels and close relatives of teasels;
b) conduct field surveys for herbivores and plant pathogens of teasels in their native range; and
c) assess the suitability of teasel herbivores and plant pathogens as BCCs and prioritize BCCs for intensive study.


2) Study the biology and host-specificity of teasel BCCs.

a) assemble a list of plant species specific to each BCC for host-specificity testing (HST);

b) perform HST on highest-priority BCCs;

i) locate, identify, and collect live BCCs from the field;

ii) rear of cultivated and wild plants to appropriate stage for testing, in synchrony with availability of appropriate stage of BCC;

iii) design bioassays specific to particular BCC-plant combinations; and

iv) assess the possible confounding presence of undescribed species or subspecies of BCCs with novel host ranges;

c) study each BCC's life cycle, including phenology of life stages, diapause cues, and interaction with host-plant; and

d) attempt to rear the BCCs in laboratory colonies.


3) Facilitate study and eventual release of appropriate BCCs by American cooperators.

a) Prepare shipments of live BCCs to American cooperators for study under quarantine conditions in the U.S.;
b) Submit petitions to USDA-APHIS-PPQ Technical Advisory Group on Biological Control Agents of Weeds (TAG) for release of appropriately tested BCCs;
c) Assist in the planning and execution of releases of TAG-approved BCCs in target weed's invaded range; and
d) Assist in the planning and execution of field monitoring of released biological control agents.


Expected Results


This research produces basic information on the biology, host-range, and damage potential of teasel BCCs with the ultimate goal of importing appropriate, effective BCCs into the U.S. for release in areas of important teasel invasion. Specific products of these efforts are expected to include:

1) improved understanding of insect biology and insect-plant interactions;
2) improved and innovative assays and techniques for determining insect host-plant specificity and impact of insect damage to its host;
3) an increase in basic knowledge in entomology and ecology, including the potential description of new species of insects and mites and improved descriptions of existing species;
4) novel application of molecular biology tools and techniques to improve the speed and efficacy of any or all of the aforementioned procedures;
5) insight into insect-rearing techniques, including rearing of taxa with little prior information or history of rearing;
6) quantities of BCCs suitable for study in the U.S. under quarantine conditions;
7) insight into growing species of wild plants that may have never been grown before;
8) quantities of TAG-approved BCCs appropriate for field release in the US.